2009 in paleontology
Birds Anfinson, O.A., Lockley, M.G., Kim, S.H., Kim, K.S., and Kim, J.Y. 2009. First report of the small bird track Koreanaornis from the Cretaceous of North America: implications for avian ichnotaxonomy and paleoecology. Cretaceous Research. . * Lockley, M., Chin, K., Houck, K., Matsukawa, M., and Kukihara, R. 2009. New interpretations of Ignotornis, the first-reported Mesozoic avian footprints: implications for the paleoecology and behavior of an enigmatic Cretaceous bird. Cretaceous Research. doi: 10.1016/j.cretres.2009.04.001. * Bell, A. and Everhart, M.J. 2009. A new specimen of Parahesperornis (Aves: Hesperornithiformes) from the Smoky Hill Chalk (Early Campanian) of western Kansas. Kansas Academy of Science, Transactions 112(1/2):7-14. Cephalopods * Fossil octopi are discovered. Newly named prehistoric cephalopods Crurotarsans * Delfino, M., and Smith, T. 2009. A reassessment of the morphology and taxonomic status of 'Crocodylus' depressifrons Blainville, 1855 (Crocodylia, Crocodyloidea) based on the Early Eocene remains from Belgium. Zoological Journal of the Linnean Society 156(1):140-167. doi: 10.1111/j.1096-3642.2009.00478.x. Newly named crurotarsans Dinosaurs Research * A new study on theropod furculae is published.Nesbitt, S.J., Turner, A.H., Spaulding, M., Conrad, J.L., and Norell, M.A. 2009. The theropod furcula. Journal of Morphology. . * A "detailed description of the skull and mandible of the Chinese cerapodan ornithischian dinosaur Jeholosaurus shangyuanensis" is published.Barrett, P.M., and Han, F.-L. 2009. Cranial anatomy of Jeholosaurus shangyuanensis (Dinosauria: Ornithischia) from the Early Cretaceous of China. Zootaxa 2072:31-55. * Knoll, F., Padian, K., and de Ricqles, A. 2009. Ontogenetic change and adult body size of the early ornithischian dinosaur Lesothosaurus diagnosticus: Implications for basal ornithischian taxonomy. Gondwana Research. . * Matthews, J. C., Brusatte, S. L., Williams, S. A., and Henderson, M. D., 2009, The first Triceratops bonebed and its implications for gregarious behavior: Journal of Vertebrate Paleontology, v. 29, n. 1, p. 286-290. * Williamson, T. E., Carr, T. D., Williams, S. A., and Tremaine, K., 2009, Early ontogeny of pachycephalosaurine squamosals as revealed by juvenile specimens from the Hell Creek Formation, eastern Montana: Journal of Vertebrate Paleontology, v. 29, n. 1, p. 291-294. * Bittencourt, J.S., and A.W.A. Kellner. 2009. The anatomy and phylogenetic position of the Triassic dinosaur Staurikosaurus pricei Colbert, 1970. Zootaxa 2079:1-56. * Chin, K., Hartman, J.H., and Roth, B. 2009. Opportunistic exploitation of dinosaur dung: fossil snails in coprolites from the Upper Cretaceous Two Medicine Formation of Montana. Lethaia 42(2):185-198. . * Maidment, S.C.R., and Porro, L.B. 2009. Homology of the palpebral and origin of supraorbital ossifications in ornithischian dinosaurs. Lethaia. . * Gates, T.A., and Farke, A.A. 2009. Biostratigraphic and biogeographic implications of a hadrosaurid (Ornithopoda: Dinosauria) from the Upper Cretaceous Almond Formation of Wyoming, USA. Cretaceous Research. . * Moratalla, J.J., and Hernán, J. 2008. Los Cayos S y D: dos afloramientos con icnitas de saurópodos, terópodos y ornitópodos en el Cretácico Inferior del área de Los Cayos (Cornago, La Rioja, España). Estudios Geológicos 64(2):161-173. . * Taylor, M.P., Wedel, M.J., and Naish, D. 2009. Head and neck posture in sauropod dinosaurs inferred from extant animals. Acta Palaeontologica Polonica 54 (2): 213–220. Hadrosaur chewing study A study titled "Quantitative analysis of dental microwear in hadrosaurid dinosaurs, and the implications for hypotheses of jaw mechanics and feeding" is published by British paleontologists Mark Purnell, Paul Barrett and student Vince Williams. The paper examined the chewing methods and diet of hadrosaurid ("duck billed") dinosaurs from the Late Cretaceous period. The scientists analyzed hundreds of microscopic scratches on the teeth of a fossilized Edmontosaurus jaw, and believe they determined exactly how a hadrosaur broke down and ate its food, which had previously eluded researchers. The study found hadrosaurs had a unique way of eating unlike any creature living today. In contrast to a flexible lower jaw joint prevalent in today's mammals, hadrosaurs had a unique hinge between the upper jaws and the rest of its skull. The team found the dinosaur's upper jaws pushed outwards and sideways while chewing, as the lower jaw slid against the upper teeth. The study also concluded that hadrosaurs likely grazed on horsetails and vegetation close to the ground, rather than browsing higher-growing leaves and twigs. However, Purnell said these conclusions were less secure than the more conclusive evidence regarding the motion of teeth while chewing. Previous studies found contradictory conclusions, and the issue remains a subject of debate. The findings were published on June 30, 2009 in the journal, The Proceedings of the National Academy of Sciences. Purnell said no previous study had ever employed this method of analyzing microscopic teeth scratches, and that the method could be used to study other areas of scientific research. New taxa Data courtesy of George Olshevky's dinosaur genera list. Bony fish * Shimada, K. and Everhart, M.J. 2009. First record of Anomoeodus (Osteichthyes: Pycnodontiformes) from the Upper Cretaceous Niobrara Chalk of western Kansas. Kansas Academy of Science, Transactions 112(1/2):98-102. Squamates Mammals Research * A study by J. R. Foster is published estimating the body masses of mammals from the Late Jurassic Morrison Formation by using the ratio of dentary length to body mass of modern marsupials as a reference. Foster concludes that Docodon was the most massive mammal genus of the formation at 141g and Fruitafossor was the least massive at 6g. The average Morrison mammal had a mass of 48.5g. A graph of the body mass distribution of Morrison mammal genera produced a right-skewed curve, meaning that there were more low-mass genera.Foster, J.R. 2009. Preliminary body mass estimates for mammalian genera of the Morrison Formation (Upper Jurassic, North America). PaleoBios 28(3):114-122. * Fujiwara, S.-I. 2009. Olecranon orientation as an indicator of elbow joint angle in the stance phase, and estimation of forelimb posture in extinct quadruped animals. Journal of Morphology. doi: 10.1002/jmor.10748. * Fujiwara, S.-I., Kuwazuru, O., Inuzuka, N., and Yochikawa, N. 2009. Relationship between scapular position and structural strength of rib cage in quadruped animals. Journal of Morphology. doi: 10.1002/jmor.10744. * Mitchell, G., van Sittert, S.J., and Skinner, J.D. 2009. Sexual selection is not the origin of long necks in giraffes. Journal of Zoology. doi: 10.1111/j.1469-7998.2009.00573.x. Plesiosaurs * O'Keefe, F. R., and Street, H. P., 2009, Osteology of the cryptocleidoid plesiosaur Tatenectes laramiensis, with comments on the taxonomic status of the Cimoliasauridae: Journal of Vertebrate Paleontology, v. 29, n. 1, p., 48-57. New taxa |style="border:0px" valign="top"| |style="border:0px" valign="top"| |- |} Pterosaurs * Lü, J. 2009. A new non-pterodactyloid pterosaur from Qinglong County, Hebei Province of China. Acta Geologica Sinica (English Edition) 83(2):189-199. doi: 10.1111/j.1755-6724.2009.00062.x. * Vullo, R., and Neraudeau, D., 2009, Pterosaur remains from the Cenomanian (Late Cretaceous) Paralic Deposits of Charentes, Western France: Journal of Vertebrate Paleontology, v. 29, n. 1, p. 277-282. New taxa |style="border:0px" valign="top"| |style="border:0px" valign="top"| |- |} Anapsids Newly named anapsids Relevant research in other sciences Evolutionary biology * A study is published that proposes that females from certain taxa use ornaments as a criterion for mate choice because other dimorphic structures, like biological "weaponry" could be used to coerce or force them to mate.Pradhan, G.R., and Van Schaik, C.P. 2009. Why do females find ornaments attractive? The coercion-avoidance hypothesis. Biological Journal of the Linnean Society 96(2):372-382. . * A study concludes that biotic factors have more pronounced local and short term evolutionary impacts than abiotic factors, which in turn have a more pronounced effect through time and on biodiversity as a whole.Benton, M.J. 2009. The Red Queen and the Court Jester: species diversity and the role of biotic and abiotic factors through time. Science 323:728-732. . Extinction A study noting the effects of the KT mass exinction on Earth's modern biota is published.Krug, A.Z., Jablonski, D., and Valentine, J.W. 2009. Signature of the end-Cretaceous mass extinction in the modern biota. Science 323:767-771. . Geology * Zhang, H., Wei, Z.-L., Liu, X.-M., and Li, D. 2009. Constraints on the age of the Tuchengzi Formation by LA-ICP-MS dating in northern Hebei-western Liaoning, China. Science in China D 52(4):461-470. doi: 10.1007/s11430-009-0052-9. Ichnology * Bedatou, E., Melchor, R.N., and Genise, J.F. 2009. Complex palaeosol ichnofabrics from Late Jurassic-Early Cretaceous volcaniclastic successions of central Patagonia, Argentina. Sedimentary Geology. doi: 10.1016/j.sedgeo.2009.04.005. Paleobiogeography Pereda-Suberbiola, X. 2009. Biogeographical affinities of Late Cretaceous continental tetrapods of Europe: a review. Bulletin de la Société Géologique de France 180(1):57-71. . Paleoecology * Nicolas, M., and Rubidge, B.S. 2009. Changes in Permo-Triassic terrestrial tetrapod ecological representation in the Beaufort Group (Karoo Supergroup) of South Africa. Lethaia. doi: 10.1111/j.1502-3931.2009.00171.x. References 2000s Category:2009 in paleontology